Reaktion #45766

Reaktionsgleichung

trimethylaluminium

hexane

ammonium chloride

ethyl 4-cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazole-2-carboxylate

hydrochloric acid

→

compound

Ausbeute 80.9%

4-Cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazole-2-carboxamide

Ausbeute 80.9%

Lösungsmittel

dichloromethane

water

dichloromethane

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.STIRRINGby stirring for 4 hours
2. 2
   Temperaturby heating
3. 3
   Temperaturunder reflux in an oil bath at 45° C. for 48 hours
4. 4
   workup.ADDITIONwas added to the reaction liquid
5. 5
   Extraktionfollowed by extraction with chloroform (100 ml×2)
6. 6
   WaschenThe organic layer was washed with saturated brine (100 ml)
7. 7
   Trocknendried over anhydrous sodium sulfate
8. 8
   Einengenconcentrated under reduced pressure
9. 9
   Sonstigethe resulting residue was purified in slurry with diethyl ether

Vorschrift

At room temperature, trimethylaluminium (4.49 ml, 4.63 mmol, 1.03 M hexane solution was added to an anhydrous dichloromethane (6 ml) suspension of ammonium chloride (247 mg, 4.62 mmol), followed by stirring at room temperature for 20 minutes. A dichloromethane (4 ml) solution of ethyl 4-cyano-7-fluoro-5-methyl-6-phenyl-1,3-benzoxazole-2-carboxylate (I-111) (500 mg, 1.54 mmol) was added, followed by stirring for 4 hours and by heating under reflux in an oil bath at 45° C. for 48 hours. With cooling with ice, 1 N hydrochloric acid (10 ml) was added to the reaction liquid, then water (20 ml) was added, followed by extraction with chloroform (100 ml×2). The organic layer was washed with saturated brine (100 ml), then dried over anhydrous sodium sulfate, concentrated under reduced pressure, and the resulting residue was purified in slurry with diethyl ether to obtain the entitled compound (368 mg, 80.8%) as a pale yellow solid.

Quelle